Expansion nail or the like



Nov. Z1, 1944. R. G. BOELTER 2,362,969

EXPANSION NAIL ORPHE LIKE Filed July s', m42

fil/42 ffy/9.

Patented Nov. 21, 1944 I UNITED STATES' f PATENT vOFFICE 2,362,969 y s f j EXPANSION NAIL on THE LIKE Rudolph G.Boelter, Chicago, Ill. Application July ys, 1942, seriarNo. 450,122

(o1. s-23)' I 2 Claims.

Y My invention relates toy a driven fastening device which is transversely expansible as an inci- A dent of its installation and toa driving tool therefor which facilitates such installation,

l An object of the invention resides in the pro,

vision of a novel, simple and effective driven fastening device or nail which is transversely expansible as an, incident of its installation -toprof 'vide an exceptionally rm .or strong bond betweenit and the structure intowhich it is driven.

With this object in View, my invention consists in certain features of novelty in the construction, combination and arrangement of parts by which 'the said object and certainy other objects, hereinafter appearing, are effected, all as fully described with reference to the accompanying drawing, and-more particularly pointed out in the appended claims.

In the said drawingy Figure 1 is a side elevation of an expansion nail embodying my invention;

Figure 2 is a cross section of the same, substantially on the line 2-2 of Figure 1';

n Figure 3 is a sidefelevati'on of a driving tol of my invention adapted to be used in driving the aforesaid expansion nail;

Figure 4 is an end elevation of the driving tool; Figure 5 isa side elevation of vthe expansion nail and driving tool in driving relation with the nail showing the nail partially driven into a structure `(shown in section) and prior'to the transverse expansion thereof as hereinafterexplained;

Figure 6 is a side elevation of ythe expansion nail in completely driven and transversely expanded condition inv the vaforesaid structure (shown in section) and Figure 7 is a side elevation` of the expansion Y nail in the partially driven condition thereof, as shown in Figure 5, but with the driving tool re- -moved pursuant to the final driving operation,

dinally and transversely. See particularly Figures l and 2. i These fastening members are provided respectively at corresponding driving ends thereof with transversely enlargeddrivingheads 'I and 8 of part circular cross section disposed I ,ber 2 is in thedesired relation with the outer surwith Vrespect'to the fastening mem-bersto cooperatively form av circular head when in transversely alined relation as shown in Figure 6.\

A plurality of pairs yof vopposingly. projecting cooperating cam formations are spaced longitu- 'dinally of the fastening members I and 2 of which the cam formations of each pair are respectively yformed integrally on the fastening members at the opposing 4or chord surfaces 3 and 4 thereof, the cam formationsof .the fasteningv member I being designated at 9 and IIJ, and thoseofthe fastening memberA 2 being designatedat II and I2, These cam form-ations of `the fastening members are alinably positionalole longitudinally of the fastening members in relative longitudinal positions thereof in which the driving heads ,'l

and 8 are'remote to4 provide a transversely oontracted relation ofthe fastening members, as illustrated in Figures; l', 2, 5 and 7, and arefoperative with relativev longitudinal movement ofthe fastening membersA from said relative positions 'toward' relative positions in'which the driving heads are transversely alined to transversely eX- pand the fastening members-from their transversely contracted relation as illustrated in Figure 6.

The pair of cam and 8, areof'greater'height or rise than the pair of cam formations I!) and I2, which are relatively adjacent the driving heads. That is to say, the lpairs ofcam' formations are graduated in height or rise toward a minimum in the direction of the driving heads, so that the fastening members I and 2 are transversely expanded into tapered relation diminishing Vtoward the driving heads as the driving heads approach transversely alined relation.k As a result, the drivingv head portions of the fasteningmembers are not transversely expanded or, at themost, they are expanded to a v minimumsextent. v A

In the driving ofthe fastening device into a structure, illustrated in Figures 5, 6 and 7, and comprising a base or wall element I3 such as may be plaster and an element I4 of other material overlying the wall for the purpose of securing the element I4 on the element I3, the fastening device is initially driven through the element I4 into the element I3-with the fastening members lI and 2 maintained in their transversely contracted driving head remote relation until the innermost driving head 8 of the fastening memface I5"of the outer element I4, say when the drivinghead 8 engages this surface as shown in 5 Figures 5' and 7. Then the fastening member I,

formations 9 .and II, which` 'are relatively remote from the driving heads ,'I

having the outermost driving head 1, is `individually driven with respect to the fastening member 2 until the driving head 'I transversely alines with the driving head 8 as shown in Figure 6. This individual driving of the fastening member I relative to the fastening member 2 causes the cams 9, III, II and I2 to transversely expand the fastening members from their initial transversely contracted .relation as .shown inEigure. 6. and thus effects .ai strong \compression l:bond .between the fastening device andv the inner element I3. By reason of the graduation of the height or rise yof the pairs of cam formations toward a minimum in the direction of the driving ends for. lheadszofithe fastening members I and 2, the fastening .mem- A.

bers, in their transversely expanded relationfform a Wedge graduating toward a'.;1ninimum,lintjthe' direction of their driving ends or heads thereby increasing the resistance against withdrawal-o1 f -the..ifasteningLilmembers; from` the :vinnereelement 113 sand f' minimizing or Aseliminating fundesirable transversezexpansionfof.. the fastening-members at ftheeouter elementifIII. ..Theinner portionspfxthe :curved outer fsurfacest rand 6 rareppreferably :provided: with transverselyiextending-teeth" .I 6 to sincreaseithisrbond.

Preferably eyieldable lsecuring :means Vis :.provided forainitia-lly securingathe fasteningg mem- 'iberszin theirtransverselycontracted relation and ewhichfisadaptedwo iperrn'itf relative movement of the fasteningzmembersras anfincident Iofindi- A"viduallyfrdriving: 4the-fastening.:member I -relative 'nto ithe :fasteningmemben 2. WAS-shown@ this lmeans cornprises:idepres`sions i lfb-formed fintthe f curved andi intowlhichi: proiectonsy I8. ofithe.- fastening member-2 are engaged, the. projections disengagndrrg stroma` theV zdepresslons'faas th e'ffasteningsmeml aber? I i iis drivenrelative;tofthef fasteningfvmember -2. fAs antaltevnativegi the'ifasteningimembers may "be 'initially ssecuredrin j: their :transversely f-contracte'di :relationibyearfrangibleobnnd such Lasi glue, Y'betvveenfl the 'chordisunfacess 3; and: 41 ofsithe .fastening members. 'The tooliof: myeinvention':isiutilizedfor initially *driving theffa'steningimemfbersfl vandi21inA their .transverselys` contractedrrelationf endg.: as show-n, "isi iintthe formiofaan 'elongated' tool; I Sihaving an r1 anvilfend 2m for 'impact'fromrar hammerand lan i opposite ,drivings `end generallyrxdesignated at .z 2 I as' illustrated linliligures",3,;41aand;5. This driving jendisprovdedwvith two axially spaced andfac- E'ingaabutment "surfaces 2 2 :andi: 23,z-1extending :von ropposite -tsides, iofraneaxialzplane .'.ofrthe .toolfjand f respectivelyl engageable V:with :the @driving tiheads 'I -vandUSI f i,thefzfasteningamembers I and:2,.aas 4iillu"strate"d "in"?Figure 5 ,'fwhenfithefasteni-ng:mem- *bersarein'their'relative-longitudinalepositionsin which they are in transverselyccontracted"relaftion Ffor #simultaneously driving ithe fastening f members *iin this f relationA as i :the iix'i'itial :idriving 'operation fAftervthis `initial idrivingcoperation, l'thefvto'ol 'fis removed `from yengagementfivvith the idr'rving; headsas` :illustrated inzlrEigure 7,-an`d: the vr'outermost Sdrivingzhead'i 'Izfisf struck lto i :driveathe Efastening member -"I relative jwtoithe fastening l member 2f-tol transversely-expand :the fastening V cardZS 'at Ithefoutergedge portionsvl thereof lin another axial planelof the tool normal to the above mentioned axial plane thereof, which shoulder formations are respectively engageable over the edges of the driving heads 'I and 8 to radially 5 confine the driving heads during the driving thereof by the tool. The driving e'nd 2I of the tool is also provided with an overhang formation 26 on and extending from the shoulder forma- ,tion .24 of..the .innermost abutment surface 22 l radially inward from this shoulder'formation and providing a shoulder surface axially spaced from `and facing this abutment surface and engage- Vable over the inner surface of the driving head 'I forQthe-:connernent of this head axially of the tool between the overhang formation and the `abutment'surface 22 for further properly positioning-.the .driving tool in driving relation with the fastening members I and 2.

iWhile I have thus described my invention, I do g notW-ishto. be. limited. to the .precisedetails described, as changesmaybe. readily Amade Without departing .fromlthe spiritof, my linvention,` .but having' thus -described my. inventiong- .clairnras new and., desire. to secure byl Letters. Patent the i fHOWng:

I. a device ,of .thecharacter described, v.the

combination of. a plurality=of elongated. correspondingly .extending fastening lmembers relative- `lyinovable longitudinallyand transversely thereof andhaving corresponding .driving ends, and a pluralityof sets of cooperating. .cam formations 4.spaced ylongitudinallypf said members and,4 graduating in.. rise. toward..a` minimum inzthedirection-.ofsaid driving ,ends and of .whichythe cam formations of each .set ...are respectively ionasaid members. atthe xopposing facesthereof, said cam formations being alinably positiona'ble. longitudinally of said members in.'relativeolongitudinal positions 4-thereof :inv/rlich ysaid driving., ends are remote to provide a transverselyV .contracted rela- Ation ofsaid members-:and operativeiW-ith relative longitudinal movement of vsaid members :from isaid' relative vpositions towardrelative positions in swhiclr-said driving ends-are less remote to transversely expand said members `into tapered? relation ldimi-nishing. V`tovvard said driving endsl 'from .-said transversely contracted relation.

'w21-Inaf-d'evice ofv-the character?describedgthe combination of twofelongated:correspondingly ex- .,tendingfffastening members-of `part circular cross section :disposed fto cooperatively lform-.a fastenfing/devicerofg generally circular cross sectionand l relativelymovable longitudinally :and ,transverse- .lyc-and1-provided respectively Aat v`corresponding ends thereof with transverselyenlarged driving ,heads of part ci-rcular cross section 'disposed-with respect to saidfmembers` to cooperatively form-a generally =circular .head when fin "transversely .alined relation,-.and;a plurality of pairssofopposingly projecting cooperating -cam lformations spaced longitudinally ofA said :members of which litl-1e .cam formations' of l each pair-are respectively onsaid-,a'nembersat the opposingf'faces thereof, @said vcam formations .being alinably position- (3a-fable."longitudinally of-.said membersin relative 7longitudinal vpositions l*thereof in which ysaid .-.driving ,lheadszare remote Ltoi provide a'trans- Aversely contracted relation -of vsaid membersv and -operative with frelative longitudinal movement .Aofisaid membersifrom'zsaid relative positions tonWard relative -positions i in "which Said driving i -headsnare transversely ialined to transversely ex- @pandY saidimembers from saidftran'sversely con- .traotedtrrelation. :RUDOLPHi G. BOEL'IER. 

